Fed Emissions vs California Emissions

codes are OBDll and available on line free..google P0496 code.

Can a loose gas cap cause code P0496?
Check the Gas Cap

The first thing you should check whenever your car has a P0496 code is your gas cap-make sure it's not loose because a loose gas cap can trigger a P0496.l

https://www.kbb.com/obd-ii/p0496/

https://www.yourmechanic.com/article/p0496-obd-ii-trouble-code-evap-flow-during-a-non-purge-condition-by-valerie-johnston

My 2001 Discovery 11 had the catalytic converters completely stopped up.. The emissions were coming into the cab.. Very dangerous.. On Ebay, there are aftermarket Catalytic converters for about $95.each. They are legal everywhere except California.. Good Luck!

If check engine light is on. Get it scanned to find the problem code. They will do this at any auto parts store for free, It may be a bad 02 sensor. Get it scanned. A vehicle can fail a state-mandated smog test because a bad, or faulty, oxygen sensor. remove the O2 sensor from the exhaust pipe ahead of the catalytic converter and look for a change in performance. Good-Day!

I didn't know Texas was exempt from federal law? Federal emissions law requires the vehicles tailpipe emissions system to be intact and in working order in order for the vehicle to be licensed for on road use. If the catalytic converter was removed and you didn't tell the buyer, the buyer can hold you responsible for all costs to repair the catalytic converter. Removing the cat will also cause a never ending check engine light do to the wrong downstream O2 sensor readings. You are better off replacing the catalytic converter with either an o.e. or a quality aftermarket unit.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Sometimes you can tell that a converter is clogged because you don't go any faster when you push the gas pedal. Also, there usually is a noticeable drop in gas mileage associated with a clogged catalytic converter.------------------------------------------------------------------------------
carbrain c168 scanner

There are two type of emission classes.

Federal and California emissions.

Look under the hood for the emission class sticker.
Smog check station's machine in CA are programmed to handle both types.

You do not need to change anything before the inspection.

==== Side notes: You should check the service record for the last Catalytic converter,O2 sensors and EGR valve change.
Service interval for
Catalytic ~180,000 miles O2 ~150,000 miles EGR ~160,000 miles


If you can locate the last smog test (even from out of state) Check for the
CO NOx

it is not legal to remove or bypass the catalytic converters.the converters do not restrict the exhaust flow to any degree because of how they are now designed and the material used in them to control emissions, if the converter is causing the light to come on then they need replacing but this should be checked out.

P0422 Buick - Catalyst below threshold.

Catalytic converter is clogged or out of medium.

Replace it.


ACTUAL DIAGNOSTIC:

Fault Code Definition
Code P0422 indicates that the Bank 1 Main Catalytic Converter's emissions efficiency has fallen below the minimum allowable limit. This threshold is tracked by a Catalyst Monitoring Oxygen Sensor located on or near the outlet of the Catalytic Converter.

Symptoms

* Check Engine Light will illuminate
* In many cases, no abnormal symptoms may be noticed

Common Problems That Trigger the P0422 Code

* Defective Catalytic Converter
* Engine misfires have damaged the Catalytic Converter
* Internal engine damage resulting in high oil consumption and/or a leaking Head gasket has damaged the Catalytic Converter

Common Misdiagnoses

* Oxygen Sensors are replaced when the real problem is a damaged Catalyst
* Catalyst is replaced when the real problem is internal engine damage, which is producing elevated emissions levels
* Catalyst is replaced when a misfiring engine is the real problem



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Catalytic Converter Removal & Installation 2.2L Engine To Remove:
Catalytic converter 2.2L engine

1. Raise and safely support the vehicle.
2. Disconnect the heated oxygen sensor (HO2S) electrical connector.
3. Remove the exhaust manifold pipe flange mounting nuts from the catalytic converter.
4. Remove the catalytic converter flange mounting nuts from the muffler.
5. Remove the catalytic converter from the muffler.
6. Remove the catalytic converter from the rear hanger bracket insulator.
7. Remove the catalytic converter.
8. Remove the (HO2S) from the catalytic converter.

To Install:

1. Install the (HO2S) to the catalytic converter.
2. Install a new gasket and the catalytic converter to the muffler.
3. Install catalytic converter to the catalytic converter hanger.
4. Install the catalytic converter flange mounting nuts to the muffler flange.
   • Tighten to 26 ft lbs (35 Nm).
5. Install the catalytic converter flange mounting nuts to the exhaust manifold pipe flange.
   • Tighten to 26 ft lbs (35 Nm).
6. Connect the heated oxygen sensor (HO2S) electrical connector.
7. Lower the vehicle.

------ Catalytic Converter Removal & Installation 4.3L Engine To Remove:

1. Raise and safely support the vehicle.
2. Raise and support the transmission.
3. Remove the transmission support
4. Disconnect the left and right pre-converter heated oxygen sensor (HO2S) electrical connector.
5. Disconnect the post-converter (HO2S) connector. Muffler flange and gasket
   
   
6. Remove the catalytic converter flange mounting nuts from the muffler.
7. Remove the catalytic converter from the muffler.
8. Remove the exhaust manifold flange mounting nuts from the catalytic converter. Catalytic converter 4.3L engine
   
   
9. Remove the catalytic converter from the support bracket insulator.
10. Remove the catalytic converter and gaskets.
11. Remove the heated oxygen sensor.

To Install:

1. Install the heated oxygen sensors as needed.
2. Install a new gasket and the Install the catalytic converter to the support bracket insulator.
3. Install the catalytic converter to the exhaust manifold flange. Install the mounting nuts.
   • Tighten to 39 ft lbs (53 Nm).
4. Using a new flange gasket, install the catalytic converter to the muffler. Install the mounting nuts.
   • Tighten to 30 ft lbs (40 Nm).
5. Connect the left and right pre-converter heated oxygen sensor (HO2S) electrical connectors.
6. Connect the post-converter (HO2S) electrical connector.
7. Install the transmission support.
8. Lower the transmission.
9. Lower the vehicle.

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It looks like you can cut them and replace them with new bolts and nuts.

my 1998 Montero Sport has 4